A SIMPLE plan may be established by which of the following entities? 1. 2. 3. Sole proprietorship with 15 employees whose wages are between $30,000 and $200,000. S corporation with 25 employees whose wages are between $10,000 and $150,000. C corporation with 110 employees whose wages are between $8,000 and $300,000. a. 1 only. b. 1 and 2. c. 2 a n d 3. d. 1,2, and 3